Explosive loads in ordnance items sometimes crack or degrade when they are subjected to environmental conditions, such as rough handling, temperature shock or even normal service use. These cracks thus formed are a source of pre-ignition or detonation when the explosive is exposed to service forces. Some conditions which also can contribute to pre-ignition are adiabatic compression of air or other gases trapped in voids such as would be produced by the formation of a cracking, or the effects of sliding surfaces, especially explosive surfaces with exposed cracks.
Explosive systems have been developed which are inherently more crack resistant than the conventional TNT-based explosive. Some systems had changes in composition such as substitution for TNT as a binder with plastic or resinous material. A binder is generally an elastomeric, resinous, or molten material in which the explosive particles are mixed. These explosive particles are generally solid crystals with little or no strength particle to particle. The "binder" acts as a glue between all the particles. The explosives designated by these changes are referred to as plastic bonded and are either pressed or cast systems. These systems, however, are expensive and economically adapted only to the more sophisticated weapon systems. The TNT systems are relatively inexpensive but have poor resistance to crack formation. With the use of the invention, improvements in strength are possible.